ROYAL FAMILY PHOTOS: William and Kate through the years

Prince George arrives for his first day of school at Thomas's school in Battersea and is met by Helen Haslem head of the lower school. (Richard Pohle/Pool Photo via AP)

Britain's Prince William accompanies Prince George as he is greeted by Helen Haslem - the head of the lower school as he arrives for his first day of school. (Richard Pohle/Pool Photo via AP)

Prince George of Cambridge, Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Princess Charlotte of Cambridge depart from Hamburg airport on July 21, 2017. (Pool/Samir Hussein/WireImage)

Prince William and his wife Kate, the Duchess of Cambridge, and their children, Prince George, and Princess Charlotte board a plane in Hamburg, Germany, Friday, July 21, 2017. (Christian Charisius/Pool Photo via AP)

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge at the Wall of Remembrance as they visit the Warsaw Rising Museum which is dedicated to the uprising of 1944. (Jane Barlow - Pool/Getty Images)

Catherine, Duchess of Cambridge, Princess Charlotte of Cambridge, Prince William, Duke of Cambridge and Prince George of Cambridge arrive at Warsaw airport during an official visit (Pool/Samir Hussein/Samir Hussein/WireImage)

President Andrzej Duda and the First Lady Agata Kornhauser-Duda greet Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge at the Presidential Palace. (Chris Jackson - WPA Pool/Getty Images)

The royal family appears on the balcony of Buckingham Palace, after attending the annual Trooping the Colour Ceremony in London, Saturday, June 17, 2017. (Kirsty Wigglesworth/AP Photo)

The royal family appears on the balcony of Buckingham Palace, after attending the annual Trooping the Colour Ceremony in London, Saturday, June 17, 2017. (Kirsty Wigglesworth/AP Photo)

The royal family appears on the balcony of Buckingham Palace, after attending the annual Trooping the Colour Ceremony in London, Saturday, June 17, 2017. (Kirsty Wigglesworth/AP Photo)

The royal family appears on the balcony of Buckingham Palace, after attending the annual Trooping the Colour Ceremony in London, Saturday, June 17, 2017. (Kirsty Wigglesworth/AP Photo)

Catherine, Duchess of Cambridge receives flowers from a boy at Place Clairefontaine during a one day visit to Luxembourg on May 11, 2017 in Luxembourg, Luxembourg. (Pool/Samir Hussein / Contributor)

Catherine, Duchess of Cambridge receives flowers from a boy at Place Clairefontaine during a one day visit to Luxembourg on May 11, 2017 in Luxembourg, Luxembourg. (Pool/Samir Hussein / Contributor)

Catherine, Duchess of Cambridge feeds a lamb as she visits Farms for City Children on May 3, 2017 in Arlingham, Gloucestershire. (Samir Hussein/WireImage)

A photo released by the Duke and Duchess of Cambridge shows their daughter, Princess Charlotte, taken in April 2017 by her at Anmer Hall in Norfolk, England. (The Duchess of Cambridge via AP)

Kate, the Duchess of Cambridge meets Dion and Danielle with baby Mia during a visit to the Ronald McDonald House Evelina in London, Tuesday, Feb. 28, 2017. (Jeremy Selwyn/Pool Photo via AP)

Kate, the Duchess of Cambridge smiles while talking to a child during a visit to the Ronald McDonald House Evelina in London, Tuesday, Feb. 28, 2017. (Jeremy Selwyn/Pool Photo via AP)

Britain's Kate, the Duchess of Cambridge receives a bouquet of flowers as she arrives at Ronald McDonald House Evelina, in London, Tuesday, Feb. 28, 2017. (Kirsty Wigglesworth/AP Photo)

Princess Kate and Prince William arrive at the British Academy Film Awards in London, Sunday, Feb. 12, 2017. (Vianney Le Caer/Invision/AP)

Princess Kate and Prince William arrive at the British Academy Film Awards in London, Sunday, Feb. 12, 2017. (Joel Ryan/Invision/AP)

Britain's Prince William speaks with Aoife, 9, during his visit to a Child Bereavement UK Centre in Stratford in east London, Wednesday, Jan. 11. (Matt Dunham, Pool/AP Photo)

Kate the Duchess of Cambridge speaks to families who have experienced bereavement during their visit to a Child Bereavement UK Centre in Stratford in east London on Jan. 11. (Matt Dunham, Pool/AP Photo)

Britain's Prince William and Kate the Duchess of Cambridge prepare to cut a cake to celebrate the one year anniversary of this charity's branch on Jan. 11. (Matt Dunham, Pool/AP Photo)

The royal family arrives for the annual evening reception for members of the Diplomatic Corps at Buckingham Palace on December 8, 2016 in London, England. (Dominic Lipinski-WPA Pool/Getty Images)

Catherine, Duchess of Cambridge, greets Bob the cat as she attends the UK Premiere of 'A Street Cat Named Bob' in aid of Action On Addiction on November 3, 2016 in London, England. (Richard Pohle - WPA Pool/Getty)

Prince William and Kate, Duchess of Cambridge at a reception for Olympians and Paralympians hosted by Britain's Queen Elizabeth II on October 18, 2016. (Yui Mok/Pool Photo via AP)

Britain's Prince William kicks a football in the simulator, watched by Kate, Duchess of Cambridge, Friday Oct. 14, 2016, at The National Football Museum, in Manchester, England. (Charlotte Graham/Pool via AP)

Prince William, Kate Duchess of Cambridge, and Prince Harry take a ride in a pod of the London Eye with members of the mental health charity "Heads Together" on October 10, 2016. (Richard Pohle, Pool Via AP)

Britain's Kate, the Duchess of Cambridge sits in on a class during a visit to the Stewards Academy on September 16, 2016. (Ian Vogler/Pool Photo via AP)

Britain's Kate, the Duchess of Cambridge meets parents, during a visit to the Stewards Academy with Prince William as part of their "Heads Together' campaign on September 16, 2016. (Ian Vogler/Pool Photo via AP)

Kate Middleton receives flowers during their visit to the Immigrant Services Society of British Columbia New Welcome Centre during their Royal Tour of Canada on September 25, 2016. (Andrew Milligan/Pool/Getty)

Kate Middleton and Prince William meet a baby in Vancouver during a visit to Sheway, a charity that helps vulnerable mothers on September 25, 2016. (Arthur Edwards/Pool/Getty)

Kate Middleton and Prince William with David Johnston, Government General of Canada and his wife Sharon Johnston at Government House on September 24, 2016 in Victoria, B.C. (Pool/Sam Hussein/WireImage)

Prince William, Kate Middleton, Prince George of Cambridge and Princess Charlotte of Cambridge arrive at the Victoria Airport in British Columbia on September 24, 2016. (Chris Jackson/Getty)

Prince George plays on a swing at Sandringham in Norfolk, England. (Matt Porteous/Handout via AP)

Prince George plays with the family dog Lupo, at Sandringham in Norfolk, England. (Matt Porteous/Handout via AP)

Prince George beckons for his mother Kate, the Duchess of Cambridge, after being lifted out of a Squirrel helicopter by his father, Prince William on Friday, July 8, 2016. (Richard Pohle/ Pool photo via AP)

Prince George, wears ear defenders as he visits with his father Prince William the Royal International Air Tattoo at RAF Fairford in England, Friday, July 8, 2016. (Richard Pohle/ Pool photo via AP)

Prince George, is lifted out of the cockpit of a red plane by his father Prince William as they visit the Royal International Air Tattoo at RAF Fairford in England, July 8, 2016. (Richard Pohle/ Pool photo via AP)

Prince George looks up at a helicopter as he visits the Royal International Air Tattoo at RAF Fairford in England on July 8, 2016. (Richard Pohle/ Pool photo via AP)

Kate, the Duchess of Cambridge, front right, applauds in the Royal Box on day eleven of the Wimbledon Tennis Championships in London, Thursday, July 7, 2016. (Kirsty Wigglesworth/AP)

Prince George meets President Barack Obama and First Lady Michelle Obama. (KensingtonRoyal/Twitter)

The royal family with President Barack Obama and Michelle Obama. (KensingtonRoyal/Twitter)

Prince William and Kate interact with a very young Assamese traditional Bihu dancer in Diphlu River Lodge, east of Gauhati, northeastern Assam state, India, April 12, 2016. (Anupam Nath/AP)

Prince William, signs visitor's book as his wife Kate, the Duchess of Cambridge looks on after paying their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

Prince William and wife Kate, the Duchess of Cambridge, paying their tributes at the India Gate war memorial on April 11, 2016.

The wreath which was placed by Britain's Prince William, and his wife Kate, the Duchess of Cambridge at the India Gate war memorial in New Delhi, India, Monday, April 11, 2016. (Manish Swarup/Pool Photo via AP)

Prince William, along with his wife Kate, the Duchess of Cambridge leaves after paying their tributes at the India Gate war memorial in New Delhi, India, Monday, April 11, 2016 (Manish Swarup/Pool Photo via AP)

Prince William and wife Kate, the Duchess of Cambridge, paying their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

Prince William, along with his wife Kate, the Duchess of Cambridge leaves after paying their tributes at the India Gate war memorial in New Delhi, India, Monday, April 11, 2016

Prince William and Kate, the Duchess of Cambridge, walk together during a visit to Gandhi Smiriti, an Indian museum dedicated to Mahatma Gandhi, on April 11, 2016. (Prakash Singh/Pool Photo via AP)

Prince William, the Duke of Cambridge, and his wife Kate, the Duchess of Cambridge, remove their shoes ahead of paying tribute during a visit to Gandhi Smiriti on April 11, 2016. (Prakash Singh/Pool Photo via AP)

Prince William, the Duke of Cambridge, and his wife Kate, the Duchess of Cambridge, remove their shoes ahead of paying tribute during a visit to Gandhi Smiriti on April 11, 2016. (Prakash Singh/Pool Photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge, centre, arrive to pay their tributes at the India Gate war memorial on April 11, 2016, (Manish Swarup/Pool Photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge pose for the media after paying their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge leave after paying their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge leave after paying their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge, right, pay their tributes at the India Gate war memorial on April 11, 2016. (Manish Swarup/Pool Photo via AP)

(Manish Swarup/Pool Photo via AP)

Prince William eats a "dosa", or a rice pancake as his wife Kate, the Duchess of Cambridge, watches during an event on young entrepreneurs in Mumbai, India, Monday, April 11, 2016. (Danish Siddiqui/Pool Photo via AP)

Britain's Prince William steers a Formula E simulator at an event on young entrepreneurs in Mumbai, India, Monday, April 11, 2016. (Danish Siddiqui/Pool Photo via AP)

Prince William and his wife Kate, the Duchess of Cambridge, remove their shoes before paying homage to Mahatma Gandhi during a visit to ''Gandhi Smriti'' in on April 11, 2016. (Kamal Singh/Press Trust of India via AP)

Prince William along with his wife Kate, the Duchess of Cambridge walk as they pay tribute during a visit to Gandhi Smiriti on April 11, 2016. (Prakash Singh/Pool photo via AP)

Britain's Prince William, along with his wife Kate, the Duchess of Cambridge interact with school children during a visit to Gandhi Smiriti on April 11, 2016. (Prakash Singh/Pool photo via AP)

Prince William along with his wife Kate, the Duchess of Cambridge speak to each other as they pay tribute during a visit to Gandhi Smiriti on April 11, 2016. (Prakash Singh/Pool photo via AP)

rince William, right, eats a "dosa" or a rice pancake as his wife Kate, the Duchess of Cambridge, watches during an event on young entrepreneurs in Mumbai, India, April 11, 2016. (Danish Siddiqui/Pool Photo via A)

Prince William, and his wife, Kate, the Duchess of Cambridge, pose after they arrive for a charity ball at the Taj Mahal Palace hotel in Mumbai, India, Sunday, April 10, 2016. (Punit Paranjpe/Pool via AP)

Britain's Prince William, and his wife Kate, the Duchess of Cambridge, greet people as they leave after their visit to a slum in Mumbai, India, Sunday, April 10, 2016. (Shailesh Andrade /Pool via AP)

Prince William, watches as his wife Kate, the Duchess of Cambridge, plays soccer during their visit to a slum in Mumbai, India, Sunday, April 10, 2016. (Shailesh Andrade /Pool via AP)

Britain's Prince William, plays soccer as his wife Kate, the Duchess of Cambridge, watches during their visit to a slum in Mumbai, India, Sunday, April 10, 2016.

Britain's Prince William, plays soccer as his wife Kate, the Duchess of Cambridge, watches during their visit to a slum in Mumbai, India, Sunday, April 10, 2016. (Shailesh Andrade /Pool via AP)

The Duke and Duchess of Cambridge, Prince William, and his wife Kate, are garlanded as they arrive at the Banganga Water Tank in Mumbai, Sunday, April 10, 2016 (Rajanish Kakade/AP)

The Duke and Duchess of Cambridge, Prince William, and his wife, the former Kate Middleton, float flowers at the Banganga Water Tank in Mumbai, India, Sunday, April 10, 2016 (Rajanish Kakade/AP)

The Duchess of Cambridge, the former Kate Middleton, plays with Indian children during a charity event at the Oval Maidan in Mumbai, India, Sunday, April 10, 2016. (Rafiq Maqbool/Pool via AP)

Prince William, center in white, and his wife Kate, walk with officials during a charity event at the Oval Maidan in Mumbai, India, on April 10, 2016. (Indranil Mukherjee /Pool via AP)

The Duke and Duchess of Cambridge, Prince William, and his wife Kate, stand after laying a wreath at the Taj Mahal Palace Hotel in Mumbai, India on April 10, 2016. (Mitesh Bhuvad/Pool via AP)

The Duke and Duchess of Cambridge, Prince William, and his wife, the former Kate Middleton lay a wreath on the martyrs memorial at the Taj Mahal Palace Hotel, April 10, 2016. (Mitesh Bhuvad/Pool via AP)

Britain's Prince William, left, along with Kate, the Duchess of Cambridge, talks with staff members at Hotel Taj in Mumbai, India, Sunday, April 10, 2016. (Rafiq Maqbool/AP Photo)

The royal family goes skiing in the French Alps on March 3, 2016. It was their first vacation as a family of four. (John Stillwell/Pool via AP)

Prince William, right, and Kate the Duchess of Cambridge pose with their children, Princess Charlotte, centre left, and Prince George while on vacation in the French Alps. (John Stillwell/Pool via AP)

Britain's Prince William poses with daughter Princess Charlotte while skiing in the French Alps on March 3, 2016. (John Stillwell/Pool via AP)

Britain's Prince William and Kate Duchess of Cambridge enjoy a snow ball fight in the French Alps on March 3, 2016. (John Stillwell/Pool via AP)

Prince William and Kate Duchess of Cambridge walk together while on vacation in the French Alps on March 3, 2016. (John Stillwell/Pool via AP)

Prince William and Kate Duchess of Cambridge enjoy a snow ball fight while on vacation in the French Alps on March 3, 2016. (John Stillwell/Pool via AP)

Britain's Prince George poses on his first day at the Westacre Montessori nursery school near Sandringham in Norfolk, England on Jan. 6, 2016. (The Duchess of Cambridge/Kensington Palace via AP)

Britain's Prince George poses on his first day at the Westacre Montessori nursery school near Sandringham in Norfolk, England on Jan. 6, 2016. (The Duchess of Cambridge/Kensington Palace via AP)

Britain's Kate Duchess of Cambridge visits the Anna Freud Centre in London on Sept. 17, 2015, in her first public engagement since Charlotte's birth. (Chris Jackson/Pool via AP)

Britain's Kate Duchess of Cambridge visits the Anna Freud Centre in London on Sept. 17, 2015, in her first public engagement since Charlotte's birth. (Chris Jackson/Pool via AP)

Britain's Kate Duchess of Cambridge visits the Anna Freud Centre in London on Sept. 17, 2015, in her first public engagement since Charlotte's birth. (Chris Jackson/Pool via AP)

Britain's Kate Duchess of Cambridge visits the Anna Freud Centre in London on Sept. 17, 2015, in her first public engagement since Charlotte's birth. (Chris Jackson/Pool via AP)

Britain's Kate Duchess of Cambridge visits the Anna Freud Centre in London on Sept. 17, 2015, in her first public engagement since Charlotte's birth. (Chris Jackson/Pool via AP)

This photo of Prince George and Prince William was released in honor of George's second birthday on July 22. The photo was taken at the christening of Princess Charlotte. (AP/Mario Testino/Art Partner/Kensington Palace)

Prince William and his wife, Kate, pose for a photo with their children after the christening of Princess Charlotte at the Sandringham Estate on July 5, 2015. (Getty Images)

Prince William and his wife Kate, the Duchess of Cambridge, pose for a photo with their families after the christening of their daughter Princess Charlotte on July 5, 2015.

Catherine, Duchess of Cambridge, and her daughter Princess Charlotte pose for a photo in the drawing room at Sandringham House after the christening. (Getty Images)

Britain's Prince George peeks into the pram of Princess Charlotte flanked by his parents in Sandringham, England, July 5, 2015. (AP Photo/Matt Dunham, Pool)

Britain's Prince William, Kate the Duchess of Cambridge, their son Prince George and daughter Princess Charlotte at St. Mary Magdalene Church in Sandringham, England, July 5, 2015. (AP Photo/Matt Dunham, Pool)